Cleaning microemulsions

In the water-flooding process, mixed emulsifiers are used. Soluble oils are used in various oil-well-treating processes, such as the treatment of water injection wells to improve water injectivity and to remove water blockage in producing wells. The same method is useful in different cleaning processes with oil wells. This is known to be effective since water-in-oil microemulsions are found in these mixtures, and with high viscosity. The micellar solution is composed essentially of hydrocarbon, aqueous phase, and surfactant sufficient to impart micellar solution characteristics to the emulsion. The hydrocarbon is crude oil or gasoline. Surfactants are alkyl aryl... 

Terpene-based microemulsion cleaning composition has been reported in some industrial applications. Oil-in-water microemulsion cleaning compositions comprising four principal components were described based on four components. These were... 

The cleaning composition may be used in concentrated or diluted form for cleaning soil from glass and metal parts, among others. This microemulsion shows that, by combining water and oil, metal surfaces can be cleaned effectively. This becomes possible because both oil- and water-soluble dirt is removed by the microemulsion. 

The same principles that lead to interest in microemulsions for displacing trapped crude oil from pores in reservoir rock also make them potentially useful for industrial cleaning [234],... 

A potent, new solvent is evolving—a supercritical carbon dioxide microemulsion. A C02-based microemulsion is especially attractive since CO2 is very abundant, relatively inexpensive, and environmentally benign at this scale of use. Applications of this system to cleaning processes appear very promising. 

The application of supercritical microemulsions to cleaning is a new area and there have been no published results to date applying these systems to cleaning operations but the combination of surfactants with fluids would be a natural choice for many systems. The information in this chapter is to be used as a guide to the development of cleaning applications based upon supercritical fluid-based microemulsions. 

Pressure-dependent effects can be exploited to significant advantage in a supercritical microemulsion-based cleaning operation. Pressure will have a strong influence on the microstructure of microemulsion phases in compressible fluids as well as on their phase behavior, Microstructure includes the size, shape, and spatial... 

Apart from obvious dry cleaning applications, potential applications of C02-based microemulsions include (i) printed circuit board cleaning, (ii) extraction of contaminants from soils, (Hi) cleaning of polymers, foams, aerogels, porous ceramics, and laser optics, (iv) regeneration of activated carbon beds or catalysts, and (v) the separation of dyestuffs from textiles. 

The opportunity to recover the surfactant and extractant following cleaning is a distinct advantage of a supercritical microemulsion over conventional water- or liquid-based systems. The low volatility... 

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